Réaction #1256739

Équation de réaction

sulfuric acid

LiAlH4

H2SO4

4-Cyanobenzoic acid

→

4-(aminomethyl)benzyl alcohol

Rendement 70.6%

4-(Aminomethyl)benzyl alcohol

Rendement 70.6%

Solvants

ether

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONwere added dropwise
2. 2
   TempératureThe reaction was heated
3. 3
   Températureto reflux for 4 hours
4. 4
   AutreThe reaction was quenched on ice with 215 mL of water
5. 5
   workup.ADDITIONfollowed by the addition of 80 g of NaOH in 650 mL of water
6. 6
   AutreThe ether was decanted off the resulting gel
7. 7
   Extractionthe gel was extracted twice with 600 mL portions of ether
8. 8
   SéchageThe combined ether fractions were dried over MgSO4
9. 9
   Autreevaporated under vacuum

Mode opératoire

Adapting the procedure described by Keppler et al., Nature Biotechnology 21, 86-89 (2003), 1.5 L of 0.5 M LiAlH4 were chilled on ice and 22 mL of concentrated H2SO4 were added dropwise. 4-Cyanobenzoic acid (10) 20 g (136 mmol) was suspended in 120 mL of ether and this was added dropwise to the sulfuric acid. The reaction was heated to reflux for 4 hours. The reaction was quenched on ice with 215 mL of water followed by the addition of 80 g of NaOH in 650 mL of water. The ether was decanted off the resulting gel and the gel was extracted twice with 600 mL portions of ether. The combined ether fractions were dried over MgSO4 and evaporated under vacuum to give 13.1 g (96 mmol) of 4-(aminomethyl)benzyl alcohol (11) as a clear oil. 1H NMR (CDCL3/TMS) δ=1.95 (broad s, 3H, —OH and —NH2, exchangeable with D2O), 3.86 (s, 2H, —CH2—NH2), 4.68 (s, 2H, —CH2—OH), 7.30 (m, 4H, aromatic).

Source